HOMA-IR Calculator for Insulin Resistance

HOMA- Insulin Resistance Explained

The HOMA-IR is being used extensively for estimates of beta cell function and insulin resistance, both in clinical practice and studies, with the caveat that it cannot be used on patients on insulin.

• HOMA-IR = (Fasting insulin in mIU/L x Fasting glucose in mg/dL) / 405

Normal reference levels for HOMA-IR range between 0.7 and 2.0. Several studies use the 2.0 value as cut-off for increased insulin resistance.

HOMA-IR is a preferred estimate for insulin resistance as glucose clamp methods, the current gold standard, are resource intensive and time consuming.

Results from several studies have shown that there is reasonable correlation between the HOMA-IR and the glucose clamp measurement, however, agreement levels have shown that there is still room for refinement before the model can be fully implemented for clinical use.

Insulin resistance defines the state in which the body does not respond to the action of insulin, therefore the normal regulatory mechanisms of glucose are impaired.

Common risk factors for insulin resistance include obesity, abdominal fat disposition, age over 45, sedentary lifestyle, hypertension. Insulin resistance can progress to pre-diabetes (A1C elevated levels) or type 2 diabetes.

QUICKI – Insulin Sensitivity

The QUICKI (Quantitative Insulin Sensitivity Check Index) model determines the subject’s level of insulin sensitivity, which is the opposite of insulin resistance. This estimation is preferred for its simplicity to the glucose clamp and the minimal model analysis.

QUICKI is defined as the inverse of the sum of the logarithms of fasting insulin and fasting glucose:

• QUICKI = 1 / [log(Fasting insulin in mIU/L) + log(Fasting glucose in mg/dL)]

QUICKI Interpretation

• >0.45: normal reference level;
• 30 - 0.45: insulin resistance likely;
• <0.30: diabetes diagnosis likely.

The linear correlation coefficient of QUICKI with SI(Clamp) is 0.78, which is better than that between SI(Clamp) and SI(MM), previously reported at 0.57.

A low insulin sensitivity value reflects greater resistance. IS values below 0.339 are associated with increased resistance and obesity and cardiovascular risk factors.

References

Original reference

Matthews DR, Hosker JP, Rudenski AS, Naylor BA, Treacher DF, Turner RC. Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man. Diabetologia. 1985; 28(7):412-419.

Katz A, Nambi SS, Mather K, Baron AD, Follmann DA, Sullivan G, Quon MJ. Quantitative insulin sensitivity check index: a simple, accurate method for assessing insulin sensitivity in humans. J Clin Endocrinol Metab. 2000; 85(7):2402-10.

Other references

Hermans MP, Levy JC, Morris RJ, Turner RC. Comparison of tests of beta-cell function across a range of glucose tolerance from normal to diabetes. Diabetes September. 1999; 48:9 1779-1786.

Wallace TM, Levy JC, Matthews DR. Use and abuse of HOMA modeling. Diabetes Care. 2004; 27(6):1487-1495.

Rabasa-Lhoret R, Bastard JP, Jan V, et. al. Modified quantitative insulin sensitivity check index is better correlated to hyperinsulinemic glucose clamp than other fasting-based index of insulin sensitivity in different insulin-resistant states. J Clin Endocrinol Metab. 2003; 88(10):4917-23.

Gutch M, Kumar S, Razi SM, Gupta KK, Gupta A. Assessment of insulin sensitivity/resistance. Indian J Endocrinol Metab. 2015; 19(1):160-4.